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Electrically conductive metal–organic frameworks (MOFs) are promising candidates for electrochemical capacitors (EC) for fast energy storage due to their high specific surface areas and potential for redox activity. To maximize energy density, traditional inorganic pseudocapacitors have utilized faradaic processes in addition to double‐layer capacitance. Although conductive MOFs are usually comprised of redox active ligands which allow faradaic reactions upon electrochemical polarization, systematic studies providing deeper understanding of the charge storage processes and structure‐function relationships have been scarce. Here, we investigate the charge storage mechanisms of a series of triazatruxene‐based 2D layered conductive MOFs with variable alkyl functional groups, Ni3(HIR3‐TAT)2 (TAT=triazatruxene; R=H, Et, n‐Bu, n‐Pent). Functionalization of the triazatruxene core allows for systematic variation of structural parameters while maintaining in‐plane conjugation between ligands and metals. Specifically, R groups modulate interlayer spacing, which in turn shifts the charge storage mechanism from double‐layer capacitance towards pseudocapacitance, leading to an increase in molar specific capacitance from Ni3(HIH3‐TAT)2 to Ni3(HIBu3‐TAT)2. Partial exfoliation of Ni3(HIBu3‐TAT)2 renders redox active ligand moieties more accessible, and thus increases the dominance of faradaic processes. Our strategy of controlling charge storage mechanism through tuning the accessibility of redox‐active sites may motivate further design and engineering of electrode materials for EC. [ABSTRACT FROM AUTHOR]

Conjugated sulfonamides (CSAs) stand out for their propitious electroactivity and notable stability in ambient conditions, making them suitable candidates for high‐potential cathode materials in lithium‐ion batteries (LIBs). This study employs a combination of machine learning, semi‐empirical quantum mechanics, and density functional theory methods to evaluate a large library of 11 432 CSA molecules, focusing on material properties crucial for application in batteries, such as synthetic complexity, redox potential, gravimetric charge capacity, and energy density. After applying the thresholds for the synthetic complexity score at 2.62 and the redox potential at 3.25 V versus Li/Li+, we identify 50 CSA molecules that are easy to synthesize and suitable for the positive electrode in LIBs. By ranking on the basis of redox potential, 13 CSA molecules having potentials greater than 3.50 V versus Li/Li+ are identified. Through further investigations using molecular dynamics simulations on these reactant molecules and their lithiated products, a molecule is singled out for synthesis and electrochemical evaluation. This molecule, lithium (2,5‐dicyano‐1,4‐phenylene)bis((methylsulfonyl)amide)(Li2‐DCN‐PDSA), demonstrates a redox potential surpassing those previously reported within the class of CSA molecules. Moreover, the study explores the quantitative structure‐property relations of CSAs, yielding insights for the development of CSA‐based LIB cathode materials, informed by the comprehensive data assembled. [ABSTRACT FROM AUTHOR]